theme: Add active, positive, neutral, negative backgrounds colors
To match what Kirigami.Theme exposes and to make them actually work.
- Inline messages are now blue instead of green.
- Got a bit of negative feedback for the “New” badge, with that I can make it use the proper positive background (light green) I wanted originally
I would really like to have this in 6.4 even if it's new api and I could imagine it breaking some themes but I'm tired of people bitching about the "new" badge because I couldn't use the design I wanted originally (positive text on positive background)
Edited by Kai Uwe Broulik